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Published on: March 29, 2010
The indirect method in the establishment of reference intervals for complement 3 and complement 4: A retrospective
Jiatong Chai1, Zeyu Sun1, Dongyang Xing1
1Department of Laboratory Medicine, The First Hospital of Jilin University, Changchun, China.
Insights
This study established new reference intervals (RIs) for complement 3 (C3) and complement 4 (C4) using an indirect method. The findings provide valuable RIs for C3 and C4, aiding clinical diagnosis in the local population.
Area of Science:
- Clinical Chemistry
- Immunology
- Biostatistics
Background:
- Reference intervals (RIs) for complement 3 (C3) and complement 4 (C4) are infrequently established, particularly using indirect methodologies.
- Accurate RIs are crucial for reliable clinical diagnosis and patient management.
Purpose of the Study:
- To establish regional reference intervals (RIs) for complement 3 (C3) and complement 4 (C4) in the Chinese population.
- To validate the indirect method for establishing C3 and C4 RIs.
Main Methods:
- Utilized a large dataset (12,313 for C3, 12,125 for C4) from a Chinese hospital database.
- Applied Tukey and Box-Cox standardization, LMS curves for age-related analysis, and a z-test.
- Employed a non-parametric approach for RI determination.
Main Results:
- Established reference intervals for C3 (0.83-1.58 g/L) and C4 (0.15-0.40 g/L).
- Found no significant sex-based differences in C3 and C4 concentrations.
- Observed a weak correlation between C3/C4 levels and age, with no significant age-related differences after statistical adjustment.
Conclusions:
- Successfully established suitable and verified reference intervals for C3 and C4 for the local population.
- Demonstrated the feasibility and practicality of the indirect method for establishing complement RIs.
- The new RIs are expected to benefit clinical diagnosis and laboratory practice.
Objective:
The establishment of reference intervals (RIs) for complement 3 (C3) and complement 4 (C4) is rare, especially by indirect methods. Therefore, this study aims to establish regional RIs for C3 and C4 by an indirect method, using relevant statistical methods.
Methods:
Total of 12,313 data points for C3 and 12,125 data points for C4 were obtained from the First Hospital of Jilin University's database in China and standardised using the Tukey and Box-Cox statistical methods. The coefficients of the skewness-median-coefficient of variation curves (LMS) were used to determine the critical value for age, and a subsequent z test used to compare the differences. A non-parametric method was used to establish the RIs.
Results:
The C3 and C4 concentrations showed no significant differences by sex, and a weak correlation with age. No significant difference was found after calculating the z value for the age points on the LMS curves. The RIs for C3 and C4 were 0.83-1.58 g/L and 0.15-0.40 g/L, respectively. The RIs all passed verification.
Conclusion:
Suitable RIs for C3 and C4 were established for the local population, and will benefit clinical diagnosis. The feasibility and practicability of the indirect method were demonstrated.
